1. Field of the Invention
The present invention relates to chip capacitors, and more particularly, to a method of manufacturing a high-frequency chip capacitor having a dielectric sheet formed of a ceramic/polymer composite.
2. Description of the Related Art
In general, as the speed and capacity of electronic apparatuses have increased, the frequency of signals transmitted along the lines of printed circuit boards has correspondingly increased. In order to transmit high-frequency signals without causing transmission loss, such as reflection loss, impedance matching between input and output terminals is of the utmost importance.
As an operating frequency increases to a high frequency, particularly, to GHz (Gigahertz), almost all the energy components of a signal between a signal line and a ground (GND) are in the form of an alternating current field. Therefore, the height or the dielectric constant of an insulating material between the signal line and the ground needs to be constant in order to minimize transmission loss such as signal reflection, due to a difference in impedance, and further, to ensure signal integrity.
As for capacitors that are used to appropriately transmit the high-frequency signals (hereinafter, simply referred to as “high-frequency capacitors”), capacitors having a small electrostatic capacity and a low-loss value are widely used.
Further, it can be said that capacitors having a small change in electrostatic capacity according to changes in temperature have very good frequency selectivity. Among multilayer ceramic capacitors (MLCCs), COG-type capacitors have these characteristics. However, as a usable frequency is higher, there is an increasing need for a capacitor that has low loss. To this end, the internal electrodes of MLCCs are formed of copper (Cu) instead of nickel (Ni) to thereby reduce loss caused by an increase in the electric conductivity of the metal.
Even though MLCCs having the internal electrode formed of the copper are advantageous in achieving low-loss capacitors, and at the same time, this composition causes a decrease in firing temperature when manufacturing capacitors. Therefore, it becomes difficult to determine an appropriate dielectric composition.